PROJECT SUMMARY Adolescents with type 1 diabetes (T1D) are at high risk for elevated diabetes distress, which greatly impacts their adherence, glycemic control (A1C), and overall quality of life (QOL). A potential barrier to improving these experiences may be that adolescents have few opportunities to develop the personal resources needed to handle adversity and manage stress. The ?Promoting Resilience in Stress Management? (PRISM) intervention is a manualized, brief, skills-based intervention delivered in 2, 45-60 minute one-on-one sessions, followed by a family meeting and supplemented by booster sessions and a digital app. PRISM was developed from Stress and Coping theory and targets skills in stress-management and mindfulness, goal-setting, positive reframing, and meaning-making. All of these skills are associated with improved patient outcomes in diverse groups of adolescent populations with chronic/serious illness, and findings from a feasibility trial in adolescents with T1D showed PRISM to be highly feasible and desirable in this population. Further, a recent pilot randomized controlled trial among adolescents with cancer suggest PRISM is associated with improved perceptions of resilience, lower psychological distress, and higher QOL. This application proposes to build on our prior experience and fill three critical knowledge gaps: (1) PRISM?s impact on A1C among adolescents with T1D; (2) PRISM?s impact on diabetes distress, self-reported adherence, and other patient-reported outcomes including resilience and QOL; and (3) the cost-effectiveness of PRISM compared to usual care in a prospective economic analysis. This funding opportunity seeks to test interventions targeting diabetes distress for impact on glycemic control. Thus, we propose a multi-site randomized controlled trial among N=120 adolescents (n=60 PRISM, n=60 Usual Care; ages 13-18) with the primary trial outcome of glycemic control 6-months post- enrollment. Time-in-range will be evaluated for participants on continuous glucose monitors as an exploratory aim. Secondary outcomes will include diabetes-distress, and patient-reported adherence, resilience, and quality of life. Cost-effectiveness will also be assessed to address the potential for sustainability and dissemination. We hypothesize PRISM will promote better glycemic control, improved diabetes distress, and be more cost-effective than usual care. This application offers an opportunity to expand the body of knowledge regarding methodologically rigorous and evidence-based interventions for adolescents with T1D. Ultimately, this research has the potential to offer a practical, skills-based curriculum designed to improve outcomes for this high-risk group.